diff --git a/test/qp-check.php b/test/qp-check.php
--- a/test/qp-check.php
+++ b/test/qp-check.php
@@ -22,9 +22,22 @@
 // $_REQUEST['_DEBUG_TEST_'] = 1;
 require_once(dirname(__FILE__) . '/../lib/util.php');
 
-$msg = get_text('vacation');
 
 echo "--------------------------------------------------\n";
+$subject = '$SUBJECT';
+$subject = 'Re: ?= $SUBJECT$SUBJECT, äöü ?=$SUBJECT';
+$subject = subject_quoted_printable_encode($subject);
+echo 'Subject: ' . $subject . "\n";
+// var_dump($subject_partsq);
+
+echo "--------------------------------------------------\n";
+
+$sencoded = $subject . '+' . $subject;
+$subject = subject_quoted_printable_decode($sencoded);
+echo 'Subject: ' . $subject . "\n";
+
+echo "--------------------------------------------------\n";
+$msg = get_text('vacation');
 $vacationa = vacation_split($msg, False);
 $subject = $vacationa[0];
 $headers = $vacationa[1];